Motion Characteristics of Microbubble in Water

Abstract

The motion characteristics of microbubble in the water or solution have important influence to crystallization process. In the paper, the movement equation of single bubble was modeled based on force equilibrium, the mechanics factors influence on the single bubble motion were discussed, and the velocity of microbubble was analysed with the different bubble sizes. The results show that the velocity of microbubble in static water is increasing with time increasing, the influence of virtual mass force and Basset force caused by the acceleration on the velocity of microbubble must be considered in the initial stage of microbubble motion. In the processes of microbubble motion, compared with constant microbubble radius the variation laws of velocity fluctuations mean with microbubble radius changing are uniform.

Microstructure controllable polyimide/MXene composite aerogels for high-temperature thermal insulation and microwave absorption

“…In the UALNF process, cavitation produced local high pressure, leading to nucleation with the introduction of ultrasound. 25 The ultrasound waves broke the cavitation bubble, generating a pressure gradient to promote nucleation. The ice crystals were broken under high temperature and pressure conditions that were triggered by the breakage of the cavitation bubbles.…”

Double Fault Parameters Estimation of Motor Based on Four-Order Cumulate of MUSIC

“…Then we use the reference signal according to the actual situation. The original signal can be equivalently represented by the formula (1), in practical application is very easy to implement [8][9][10] .…”

Ultrasound‐assisted freeze‐drying strategy to enhance nanoparticle dispersion in aerogels: A case study on polyimide/silica nanocomposite aerogel

“…For example, compared with the co‐gel method, which requires hydrolysis of silica source precursors, UAFD avoids the tedious silica solution preparation process and optimizes the preparation path of composite aerogels. At the same time, UAFD greatly improves the freezing efficiency by affecting the primary nucleation stage and inducing nucleation by local high pressure generated by cavitation 10,11 . In addition, the ultrasonic effect on the secondary nucleation stage enhances the thermal insulation of the composite aerogel by crushing the large‐sized crystals through the micro‐fluidization generated by the mechanical interaction, the local high temperature and pressure generated by the cavitation effect to produce porous structures with smaller pore size 12,13 .…”

“…At the same time, UAFD greatly improves the freezing efficiency by affecting the primary nucleation stage and inducing nucleation by local high pressure generated by cavitation. 10,11 In addition, the ultrasonic effect on the secondary nucleation stage enhances the thermal insulation of the composite aerogel by crushing the largesized crystals through the micro-fluidization generated by the mechanical interaction, the local high temperature and pressure generated by the cavitation effect to produce porous structures with smaller pore size. 12,13 Moreover, UAFD permits the preparation of composite aerogels with higher surface roughness to enhance hydrophobicity 14 and thus achieve further improvement in the overall performance of thermal protection materials.…”